Numerous conventional formulations such as cosmetic formulations for providing benefits, including, for example, absorbing water, modifying feel, thickening the formulation, and/or protecting skin, include oxygen sensitive compounds with high oxidative potential, such as retinol (vitamin A), ascorbic acid (vitamin C), tocopherol (vitamin E), resveratrol, polyphenols, polyphenol-rich ingredients such as legumes, fruits (e.g., apples, blackberries, strawberries, and the like, and combinations thereof), vegetables (e.g., broccoli, cabbage, celery, onion and parsley), red wine, chocolate, green tea, olive oil, bee pollen, essential fatty acids (e.g., omega-3 and omega-6 fatty acids), omega-rich ingredients such as fish oils and flax seed oils, and vitamin C-rich ingredients such as rose hip oils. These compounds are extremely good antioxidants that are beneficial for the formulation and to consumers as they neutralize free radicals, provide anti-aging benefits, nourish the skin, and provide various other benefits. Even with the multiple benefits of these compounds, because of their antioxidant potential, many of these compounds are inherently unstable to oxidative conditions and therefore, a formulation including these compounds typically requires one or more processing conditions to prevent the exposure of these sensitive actives to oxidative conditions that could cause these compounds to lose activity or modify over time. For example, in many formulations, the addition of stabilizers for extending the formulation's shelf life has been found desirable.
Furthermore, the above-described formulations are currently prepared in a batch-type process, either by a cold mix or a hot mix procedure. The cold mix procedure generally consists of multiple ingredients or phases being added into a kettle in a sequential order with agitation being applied via a blade, baffles, or a vortex. The hot mix procedure is conducted similarly to the cold mix procedure with the exception that the ingredients or phases are generally heated above room temperature, for example to temperatures of from about 40 to about 100° C., prior to mixing, and are then cooled back to room temperature after the ingredients and phases have been mixed. In both procedures, the oxygen sensitive compounds (and, their respective stabilizers) are added to the other ingredients manually by one of a number of methods including dumping, pouring, and/or sifting.
These conventional methods of mixing oxygen sensitive compounds into formulations have several problems. For example, inappropriate handling of the sensitive compounds and other ingredients can lead to espousing the ingredients to an oxidizing atmosphere before mixing. Furthermore, by using one of the above described batch procedures, several hours are required to complete the process, which can not only be extremely expensive, but can also increase the chance of exposing the oxygen sensitive compounds and other ingredients to oxidizing conditions.
Based on the foregoing, there is a need in the art for a treatment system that provides ultrasonic energy to treat formulations to improve shelf life. Specifically, there is a need for a treatment system that can both remove effluent gas, such as oxygen, from a formulation to prevent exposure of oxygen sensitive compounds to oxidative conditions and/or sufficiently mix stabilizers and other components into the formulation to improve shelf life.